Michael B. Stone

Point-of-care ultrasound evaluation of pericardial effusions: does this patient have cardiac tamponade?

Detection of pericardial effusions using point-of-care focused echocardiography is becoming a common application for clinicians who care for critical patients. Identification of tamponade physiology is of great utility, as these patients require urgent evaluation and management. We describe techniques that the point-of-care clinician sonographer can use to determine the presence or absence of echocardiographic evidence of cardiac tamponade.

Pain Control in Disaster Settings: A Role for Ultrasound-Guided Nerve Blocks

INTRODUCTION Acute pain management for patients sustaining injuries in natural disasters and complex emergencies should be a priority for medical providers. Although there are minimal data examining the modalities and effectiveness of pain control in disaster settings, what data exist reveal practices that would be considered grossly inadequate in a typical emergency department (ED) setting. Ultrasound-guided nerve blocks performed by emergency physicians who have undergone targeted training have the potential to positively affect pain control and safety for patients with traumatic injuries in disaster settings. Femoral, popliteal, forearm, and interscalene blocks have been used safely and successfully in the ED setting for fracture reduction and splinting, incision and drainage, and complex wound care, procedures frequently required in disaster settings. The inherent difficulties of disaster settings do raise challenges to documentation, sterile technique, and monitoring for adverse effects such as local anesthetic systemic toxicity (LAST) that will require further investigation. Emergency physicians, already trained in procedural ultrasound skills and frequently required to perform extremity procedures in daily practice, are positioned to rapidly gain training and proficiency with nerve blocks. Once mastered, ultrasound-guided nerve blocks have the potential to greatly improve pain control in disaster settings, as well as in the general practice of emergency medicine. Ultrasound-guided nerve blocks are being increasingly introduced into emergency medicine practice to provide pain control for patients presenting with traumatic injuries and those undergoing painful procedures. The challenges to pain control in disaster and resource-limited settings make ultrasound-guided nerve block particularly applicable in these settings as a central component of a multimodal approach to pain management. Emergency ultrasoundguided nerve blocks have proven utility in combat and disaster settings, using the deposition of local anesthetics around peripheral nerves to induce a reversible loss of sensation with minimal central nervous system and cardiovascular adverse effects. Emergency ultrasound-guided nerve blocks differ from the traditional practice of perioperative regional anesthesia, however, in having a primary goal of acute pain reduction in the setting of n

Ultrasound-guided intercostal nerve block for traumatic pneumothorax requiring tube thoracostomy

A 39-year-old woman presented to our emergency department 3 days after an assault. Initial evaluation demonstrated a right pneumothorax. Given her hemodynamic stability, a series of ultrasound-guided intercostal nerve blocks were performed. The indications, technique, and advantages of this approach are reviewed. A 39-year-old woman with a past medical history of intravenous drug use presented to the emergency department (ED) with chest pain and shortness of breath. She reported being assaulted 3 days prior and leaving against medical advice from another ED yesterday after being diagnosed with a “collapsed lung.”Her vital signs were pulse 118/min, blood pressure 115/72 mm Hg, respirations 24/min, temperature 37.1 degrees, and oxygen saturation 95% while breathing room air. Physical examination revealed decreased breath sounds on the patients right side without crepitus, tracheal deviation, or flail segments. A focused bedside ultrasound demonstrated absent pleural sliding in the anterior, lateral and posterolateral right hemithorax. A portable anteroposterior upright chest radiograph confirmed the diagnosis of large (N50%) pneumothorax. Given the patients hemodynamic stability, the treating emergency physicians performed ultrasoundguided intercostal nerve blocks at the right third through seventh intercostal spaces to decrease pain during and after tube thoracostomy placement. The patient was positioned prone, and the spinous processes of the thoracic vertebrae were identified by palpation. After sterile preparation, a 13-6 MHz high-frequency linear transducer (SonoSite SFAST, Bothell WA) was placed in a longitudinal parasagittal orientation to identify the ribs and pleural line. After subcutaneous infiltration with local anesthetic, a 22-gauge needle attached to a control syringe was advanced using an in-plane technique (Fig. 1). The needle was visualized approaching the inferior margin of the target ribs, and 3 mL of 0.5% bupivicaine with epinephrine was injected into each intercostal space with real-time ultrasound visualization of local anesthetic spread to the adjacent pleura (Fig. 2). 0735-6757/

The Ultrasound-guided “Peripheral IJ”: Internal Jugular Vein Catheterization using a Standard Intravenous Catheter

– see front matter

Three-view bedside ultrasound for the differentiation of acute respiratory distress syndrome from cardiogenic pulmonary edema

BACKGROUNDnObtaining vascular access is difficult in certain patients. When routine peripheral venous catheterization is not possible, several alternatives may be considered, each with its own strengths and limitations.nnnDISCUSSIONnWe describe a novel technique for establishing vascular access in Emergency Department (ED) patients: the placement of a standard catheter-over-needle device into the internal jugular vein using real-time ultrasound guidance. We present a series of patients for whom this procedure was performed after other attempts at vascular access were unsuccessful. In all cases, the procedure was performed quickly and without complications.nnnCONCLUSIONnAlthough further study of this technique is required, we believe this procedure may be a valuable option for ED patients requiring rapid vascular access.

Identification and correction of guide wire malposition during internal jugular cannulation with ultrasound.

Bedside ultrasound is being increasingly used by emergency physicians (EPs) for the differentiation of acute dyspnea in critically ill patients. Lung ultrasound is emerging as a highly sensitive tool in diagnosing alveolar interstitial edema with the presence of diffuse “B-lines” arising from the pleural line. However, when used independently, lung ultrasound is unable to differentiate between cardiogenic and noncardiogenic causes of pulmonary edema. This case report describes a rapid 3-view or “triple scan” sonographic examination to differentiate acute respiratory distress syndrome (ARDS) from cardiogenic pulmonary edema.

Accuracy of emergency physicians using ultrasound measurement of crown-rump length to estimate gestational age in pregnant females

Real-time ultrasound guidance for central venous catheterization increases success and reduces procedural complications. I describe a case in which guide wire resistance was encountered and real-time ultrasound visualization of the guide wire facilitated correction of guide wire malposition. No additional passes of the introducer needle were necessary and the chances of inadvertent carotid artery puncture or pneumothorax were therefore reduced. The technique described here may prove valuable when guide wire resistance is encountered while placing a central venous catheter.

Performance accuracy of hand-on-needle versus hand-on-syringe technique for ultrasound-guided regional anesthesia simulation for emergency medicine residents.

STUDY OBJECTIVEnThe objective of this study is to evaluate the accuracy of emergency providers (EPs) of various levels of training in determination of gestational age (GA) in pregnant patients using bedside ultrasound measurement of crown-rump length (CRL).nnnMETHODSnWe conducted a prospective, cross-sectional, observational study of patients in obstetrical care at an urban county hospital. We enrolled a convenience sample of women at 6 to 14 weeks gestation as estimated by last menstrual period. Emergency providers used ultrasound to measure the CRL. Repeat CRL measurements were performed by either an obstetrical ultrasound technician or senior obstetrician and used as the criterion standard for true GA (TGA).nnnRESULTSnOne hundred five patients were evaluated by 20 providers of various levels of training. The average time required to complete the CRL measurement was 85 seconds. When CRL measurements performed by EPs were compared with the TGAs, the average correlation was 0.935 (0.911-0.959). Using standard accepted variance for CRL measurements at different GAs according to the obstetrics literature (±3 days for 42-70 days and ±5 days for 70-90 days), correlation between EP ultrasound and measured TGA was 0.947 (0.927-0.967).nnnCONCLUSIONSnEmergency providers can quickly and accurately determine GA in first-trimester pregnancies using bedside ultrasound to calculate the CRL. Emergency providers should consider using ultrasound to calculate the CRL in patients with first-trimester bleeding or pain because this estimated GA may serve as a valuable data point for the future care of that pregnancy.

Diagnosing centrally located pulmonary embolisms in the emergency department using point-of-care ultrasound

Introduction Ultrasound-guided nerve blocks (UGNB) are increasingly used in emergency care. The hand-on-syringe (HS) needle technique is ideally suited to the emergency department setting because it allows a single operator to perform the block without assistance. The HS technique is assumed to provide less exact needle control than the alternative two-operator hand-on-needle (HN) technique; however this assumption has never been directly tested. The primary objective of this study was to compare accuracy of needle targeting under ultrasound guidance by emergency medicine (EM) residents using HN and HS techniques on a standardized gelatinous simulation model. Methods This prospective, randomized study evaluated task performance. We compared needle targeting accuracy using the HN and HS techniques. Each participant performed a set of structured needling maneuvers (both simple and difficult) on a standardized partial-task simulator. We evaluated time to task completion, needle visualization during advancement, and accuracy of needle tip at targeting. Resident technique preference was assessed using a post-task survey. Results We evaluated 60 tasks performed by 10 EM residents. There was no significant difference in time to complete the simple model (HN vs. HS, 18 seconds vs. 18 seconds, p=0.93), time to complete the difficult model (HN vs. HS, 56 seconds vs. 50 seconds, p=0.63), needle visualization, or needle tip targeting accuracy. Most residents (60%) preferred the HS technique. Conclusion For EM residents learning UGNBs, the HN technique was not associated with superior needle control. Our results suggest that the single-operator HS technique provides equivalent needle control when compared to the two-operator HN technique.

Ultrasonographic infection control practices in the emergency department: a call for evidence-based practice.

Objective: The study objective was to investigate the combined accuracy of right heart strain on focused cardiac ultrasound (FOCUS) and deep vein thrombosis (DVT) on compression ultrasound (CUS) for identification of centrally located pulmonary embolism (PE) diagnosed on computed tomography pulmonary angiography (CTPA). Methods: This was a prospective observational study using a convenience sample of patients undergoing CTPA in the emergency department (ED) for evaluation of PE. Patients received a FOCUS looking for right heart strain (McConnells sign, septal flattening, right ventricular enlargement or tricuspid annular plane systolic ejection (TAPSE) < 17 mm) and a CUS looking for DVT. Ultrasounds were interpreted by both the investigator performing the ultrasound and the principal investigator independently. Results: There were 199 patients enrolled in the study, with 46/199 (23.1%) positive for a PE. Of these, 20/46 (43.5%) PEs were located centrally. Of those with a PE, 20/46 (43.5%) had an associated DVT identified on bedside ultrasound. Among patients with a proximal PE, 18/20 (90.0%) had evidence of right heart strain and the combination of lower extremity CUS and FOCUS was 100% sensitive. Diagnostic accuracy of ultrasound was much lower for peripherally located PEs. Conclusions: Emergency physician‐performed bedside ultrasound may be sufficient to exclude the presence of centrally located PE, as the sensitivity in this study was 100%. Additionally, several patients with PE may qualify for early anticoagulation when DVT is identified, and further research in indicated to determine whether these patients ultimately require CTPA given identical treatment algorithms in the absence of RV strain or biomarker elevation.